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1 M. SOPRANI PIANO KEY ACTION FOR ACCORDIONS Filed Feb. 3, 1930 36:23 9292 coon-e08 on 0e8- 2:2! 2- cos 2:28 a: :5 2-2::- 2-33 83 :3 82:08 22-2822- 22- 09 008 so: 28- 0 0 008 on :3

Patented Dec. 9, 1930 PATENT OFFICE MARIO SOPRANI, F CAJSTELFIDARDO,ITALY PIANO-KEY ACTION FOR ACCORDIONS Application filed February 3,1930. Serial No. 425,476.

My invention relates to accordions and particularly to the piano keyaction and supporting key board structure therefor.

An important object of the invention is to 6 eliminate the use of woodfor supporting the keys by providing a key supporting board or frameconstructed of light sheet metal such as aluminum.

A further object is to provide a sheet metal key supporting board whichalthough of light weight is very strong and rigid and on which the keysmay be readily assembled and held in accurate alignment.

Another important object of the invention is to eliminate the use ofwood in the key structure and substitute light metal such as aluminum.

Another object is to provide key bodies formed or molded of celluloid,bakelite, or other special material or composition which is durable andlight.

Another important feature is to reduce as much as possible the amount ofmaterial in thekey body in order to procure lightness, but to distributethe material so that the necessary strength will be provided to hold thekey body rigid against flexing or distorting.

A further object is to rovide an integral metallic key lever in the ormof a metal rod for supporting a valve at one end and at its other endbeing shaped to be readily secured to the key body to form a rigidsupport therefor, the outer end of the lever being preferably flattenedand the key body being provided with grooves or""passageways into whichthe flattened end may be readily received and secured so that the leverwill support and reinforce the key body.

The above enumerated features and other features of my invention areincorporated in the structure shown on the drawings, in which drawings;

Figure 1 is a plan view of an accordion with parts removed to disclosemy improved key board and key structure arrangement;

Figure 2 is a section on plane 11-11 of Figure 1;

Figure 3 is an underside view of a key structure;

Figure 4 is an enlarged section on plane IVIV of Figure 3; and

Figure 5 is a similar section, showing a modified arrahgement.

On the structure shown, the rectangular frame 10, which is usually ofwood, forms the inner head or chest between which and an outer head orchest (not shown) is interposed the bellows 11. The outer end of thisframe is closed by a metal plate 12 which may be of aluminum, and theplate is sup ported on lugs or brackets 13 extending from frame 10. Theplate has properly arranged ports or air passages 14 which communicatewith the tone producing units (not shown), usually in the form of reedstructures. To insure accurate and air tight seating for the reed units,the inner side of the plate 14 is provided with a layer or lining 15 ofmaterial such as soft leather.

Extending at the proper angle from the frame 10 is the rectangular frame16, usually of wood, for the keyboard structure, the two frames beingsuitably secured together. 'Fitting within the frame 16 and forming abottom therefor, is the sheet metal frame or key board 17 for supportingthe piano key struc ture. This frame may be in the form of a flat plateof metal such as aluminum and has its end sections deflected to form theend so flanges 18, the front flanges 19, and the rear flange 20, thisflange 20 being at an angle so that it will fit againstthe plate 12 towhich it is rigidly secured as by riveting, welding, or otherwise, sothat the plate 12 and the frame 17 will form a rigid metallic structurefor reinforcing the wood frame work 10 and 16. The key board frame 17may be rigidly secured to the frame 16 as by means of screws 21.Adjacent to its rear edge the plate has struck u wardly therefrom a rowof cars 22 having a igned openings for receiving a fulcrum rod 23 whichmay be in the form of a length of 'wire. This rod may readily beinserted through one end flan e 18 and extended through the openings 0the cars 22 and with its end then extending through the opposite endflange to be supported thereby so that the rod, when inserted, will berigidly l supported by the frame 17 in proper alignment to form afulcrum support for the natural or white keys 24 and the accidental orblack keys 24, these keys being grouped and arranged to form the pianokey assembly, as is well understood in the art. To assist in properlygrouping the keys, the ears 22 are spaced accordingly.

Each key is supported by a lever structure or L, whose outer and innersections 25 and 25 are at an angle with each other, the outer ends ofthe levers supporting the key bodies and the inner ends of the leverssupporting the valves 26. As clearly shown in Figure 1, the valves forthe white keys control the ports 14 along the outer section of the plate12, and the valves for the black keys control the ports 14' along theinner section of'the plate.

The key levers may be formed integral from lengths of wire of suitablematerial, such as aluminum which is strong and light. The outer section25 of each lever is formed by flattening the wire to rectangularcrosssection so that these outer sections are of flat bar shape asclearly shown in Figures 4 and 5.

The bodies of the keys are preferably formed integral by being moldedfrom suitable material such as celluloid or phenol condensationproducts. As shown, the body of each white key comprises a top orfingering plate 27 with lugs 28 depending therefrom and adapted tosecurely receive the front end 25 of the supporting lever. As shown inFigure 4, these lugs may have aligned vertical slots 29 open at theirlower ends for the lateral insertion and reception of the flat leverends. In the arrangement shown in Figure 5, the lugs have aligned closedpassageways 30 through which the lever end may be insertedlongitudinally of the key body. The lug 28' at the front end of eachwhite key may be longer than the other lugs in order to give addedstrength to the outer end of the key, and a finish or end flange 31 isprovided at the outer end of the lug 28 and set inwardly a distance fromthe outer end of the fingering top 27, this flange forming also a stopfor gauging the position of the lever supporting end 25 when itvisapplied to the key body. The black key bodies are secured to theirsupporting levers in a manner similar to that provided for the whitekeys.

Near its inner end, each lever section 25 has an opening 32 therethroughfor the insertion of a bearing bushing 33 which may be a short length oftubing. These bushings receive the fulcrum rod 23, the rod beinprogressively inserted through the bushings as the keys areprogressively assembled on the key board. The bushings, b formingextended bearings, will hold the ey structures against lateral rockingor displacement, and the bushings may abut each other and the ears 22 sothat the key structures will be held against lateral shifting on thefulcrum rod, and with their valves at all times in accurate alignmentand cooperative position relative to the valve ports 14 to control theflow of air for the reed units.

A suitable spring structure 34 is provided for each key structure tonormally hold the key body in its upper position and the correspondingvalve seated against the plate 12. The spring structure shown is U-shapewith its upper leg secured at its end to the key body and its lower legabutting against the inner side of the key board frame 17, as clearlyshown in Figure 2.

To assist inguiding the movement of the key structures and maintain thelateral alignment thereof on the key board, guide ribs or walls 35 areprovided with guide slots 36 which receive the ends 25 of the keylevers. These guide walls may be of aluminum and may have flan es 37 bymeans of which they may be secured to the key board frame 17 byriveting, welding, or otherwise.

The all-metal key supporting frame 17 together with the metal valveplate 12 to which it is secured forms a very rigid but light metalreinforcement for the ac ordion structure and holds the key board in"accurate alignment with the valve seating plate and prevents distortionso that the valves will always be accurately seated. The elimination ofwood from the key structure and the support and reinforcement of the keybodies by the integral metal key levers produces a very strong andrigid, yet light structure, and the key top or fingering surfaces willalways remain straight and fiat and in accurate alignment with eachother.

Although I have shown and described one practical and efficientembodiment of the fea tures of my invention, it is to be understood thatchanges and modifications may be made without departing from the scopeand rinciples of the invention, and I do not, t erefore, desire to belimited as is specified in the appended claims.

I claim as follows:

1. The combination of a sheet metal valve plate, a sheet metal keysupporting frame extending from and rigidly secured to said valve plate,sections deflected from said frame forming a row of upstanding ears onsaid frame, a fulcrum rod supported by said ears, integral metallic keylevers fulcrumed on said rod, valves on said key levers for cooperatingwith ports through said valve plate, and key bodies mounted on the outerends of said levers.

2. In a musical instrument of the class described, a valve plate havingair ports, a key supporting frame constructed of sheet metal and rigidlysecured to said valve plate, a row of ears integral with and deflectedfrom said frame, a fulcrum rod supported by said ears, key leversfulcrumed on said rod, and valves on said key levers for cooperatingwith said ports.

3. In a musical instrument of the class described, the combination withthe instrument body, a valve plate on said body having ports, a keyboard extending from said body, said key board being constructedentirely of light sheet metal, a row of cars deflected from said keyboard, a fulcrum shaft supported by said ears, keys fulcrumed on saidrod, valves on said keys for cooperating with said ports, and slottedsheet metal ide walls for said keys secured to said key oard.

4. In a musical instrument of the class described, the combination of asheet metal valve plate having orts, a key supportin frame constructed 0sheet metal and secured to said valve plate, sections deflected upwardlyfrom said ey su porting frame to form a longitudinal row 0 ears, afulcrum rod sup ported b said ears, integral metallic key levers fucrumed on said rod, valves on the inner ends of said levers forcooperating with said ports, and inte ral key bodies mounted on theouter ends 0% said levers.

5. In a musical instrument of the class described, the combination of apiano key board, a fulcrum rod supported on said board, key

7 levers fulcrumed on said rod, each lever being a length of wire havingits outer end flattened and disposed in a plane at right angles withsaid'board, a key body for each lever having passageways for receivingthe flattened end thereof to be thereby secured thereto, and valvescontrolled by said key levers.

6. In a musical instrument of the class described, the combination of akey board, a fulcrum shaft on said board, a plurality of piano keylevers fulcrumed on said rod, each lever being a length of wire havingits outer end flattened and disposed in a plane at right angles withsaid board, a key body for each lever comprising a fingering top and aplurality of ugs extending there om having passageways therethrough forreceiving the flattened end of the respective lever, and valvescontrolled by said key levers.

7. In a musical instrument of the class described, the combination of apiano key board a fulcrum rod on said board, a lurality of piano keylevers fulcrumed on sald rod, each lever being a length of wireflattened at its outer end and disposed in a plane at right angles withsaid board, an integral key body for each lever comprising a fingeringtop and lugs extending downwardly therefrom, said lugs havingpassageways for receiving the flattened end of the lever, and valvescontrolled by said key levers.

8. In a musical instrument of the class described, the combination of apiano keyboard, a row of key levers fulcrumed intermediate their ends onsaid board, a fingerin plate for each lever having a row of aperturelugs depending therefrom and the front end of the lever extendingthrough said lugs to reinforce and support the ngering plate and valvessupported by the other ends 0 said levers.

9. In a musical instrument of the class described, the combination of apiano keyboard, a row of piano key levers fulcrumed intermediate theirends on said board, fingering plates for said levers having de endingapertured lugs, said levers at their ront ends being of pol gonal crosssection and extending through t e lugs of the respective fingeringplates to reinforce and support the plates, an valves engaged by therear ends of said levers.

In testimony whereof I have hereunto subscribed my name at Chicago, CookCounty,

Illinois.

MARIO SOPRANI.

